#set
#Create
#add
s = set()
s.add("b")
print(s)

#dir(s)查看函数


#Retrieve
"b" in s
True


#Update
s.update("b", "d")
print(s)


#union
m = {"s"}
n = {"d"}
m.union(n)
{'s', 'd'}
m.union("tttt")
{'t', 's'}
m.union({"tttt"})
{'s', 'tttt'}


dd = {"q", "e", "p"}
print(s.union({"dd"}))


#delete
#remove
dd.remove("q")
print(dd)


#discard
dd.discard("e")
print(dd)


#pop
dd.pop()
print(dd)